It's been over two years since Ethereum's community last rallied behind a big tech event. That event—the so-called Ethereum merge—marked the network's long-awaited shift to a new, more eco-friendly consensus mechanism called "proof-of-stake."
The core guts of the Ethereum blockchain have changed little since then. The chain's developers have pushed through a series of upgrades to enable the growth of quick and cheap "layer-2" blockchains, but the Ethereum community has mostly been starved of a single organizing vision—at least one that commanded the level of enthusiasm generated by the Merge.
That might soon change.
At Ethereum's Devcon conference in Bangkok on Tuesday, Ethereum Foundation researcher Justin Drake revealed his proposal for a major redesign of Ethereum's consensus layer called "Beam Chain."
Beam Chain is "a proposed redesign of the consensus layer that incorporates all of the latest and greatest ideas from the Ethereum roadmap," Drake said in a speech at Bangkok's Queen Sirikit National Convention Centre.
Drake's Beam Chain vision organizes a series of "big ticket" upgrades to Ethereum's consensus layer into a single package. The changes include adjustments to Ethereum's block production apparatus, as well as how it handles staking and zero-knowledge cryptography.
Drake's presentation was highly anticipated—coming after months of speculation online and in crypto forums that the influential Ethereum researcher, who was instrumental to the 2022 Merge upgrade, was working on something major. Drake delivered his remarks to a packed convention hall, with onlookers spilling out into the hallway outside of the event's main stage.
The Beam Chain won't entail any immediate changes to Ethereum, or even anything radically different from what's already on the chain's roadmap. It does, however, propose a major change to how Ethereum's future upgrades are organized.
Today, Ethereum upgrades its core code roughly once per year. Drake proposes continuing to make incremental upgrades to the chain each year to address "low-hanging fruit," but then knocking out big changes in one fell swoop a few years from now.
The Beam Chain would focus on Ethereum's consensus layer, also called the Beacon Chain, which is the part of the network that handles how transactions get processed and recorded. "The beacon chain is kind of old," Drake said. "The spec was frozen five years ago, and in those five years so much has happened."
According to Drake, the Ethereum developers today have a "much better understanding" of how to adapt to maximal extractable value—strategies used by sophisticated traders to wring extra profit from Ethereum, sometimes at the cost of regular users. The past half-decade has also yielded valuable breakthroughs in zero knowledge technology, said Drake, and the Ethereum blockchain has built up "technical debt" that challenges developers' ability to develop the chain quickly and securely.
Among the focus areas for the Beam Chain will be "faster slots" and "faster finality," meaning ramping the frequency with which blocks are added to the chain, as well as increasing the number of transactions included per-block. This could eventually mean the introduction of single slot finality, where blocks with transaction data can be finalized immediately, meaning that information would become permanent right away and impossible to alter.
Currently, it takes about 15 minutes on Ethereum for a block to finalize. By decreasing the finality time, the finalization process would become more efficient for applications or exchanges that have a high transaction throughput. Having that 15 minute delay creates opportunities for MEV to be extracted and raises the risk of reorgs.
However, there are some concerns about centralization with faster finalization times, since there's more computing power needed, with expensive hardware. Developers will need to balance the tradeoff between shortening finalization times and computing power.
The Beam Chain also includes a proposal to bake zero-knowledge cryptography deeper into the fiber of Ethereum's base network.
Ethereum developers have embraced a roadmap involving layer-2 rollups, which are auxiliary blockchains atop Ethereum where transactions can be executed quickly and at a lower cost, and then settled down to the base chain.
As part of that, rollups have embraced a new type of technology that uses zero-knowledge proofs to help with the scaling of the blockchain. Over the last two years, dozens of ZK rollups have popped up, like Polygon’s zkEVM and Matter Labs zkSync, initially driving a lot of the attention and building to these new blockchains.
With Drake’s Beam Chain proposal, support for zero-knowledge proof will be built into the main Ethereum layer-1 chain. It's therefore reasonable to wonder what implications this might hold for the fast-growing field of ZK-powered layer-2 networks.
While the Beam chain would be an ambitious upgrade, Drake said in his talk on Tuesday that he was reluctant to call it "Ethereum 3.0" (people sometimes referred to Ethereum's 2022 Merge upgrade as "Ethereum 2.0.") "The Beam Chain is only about the consensus chain," said Drake, while other research is still being done into Ethereum's execution and data layers—the other core elements of the network that support things like apps and layer-2 data.
